Intake manifold



June 6, 1939. D. A. SULLIVAN 2,150,922

INTAKE MANIFOLD Filed Aug 14, 1936 2 Sheets-Shet 1 INVENTOR DONNELL' A. SULLIVAN.

June 6, 1939. D. A. SULLIVAN ,160,922

- INTAKE MANIFOLD I Filed Aug. 14, 1936 2 Sheets-Sheet 2 BY W ToimaYes.

Patented June 6, 1939 UNIT ED stares. gnrsur or ies.

V I 2,160,922. I

INTAKE? MANIFOLD; DonnellA. Sullivan, Dearborn, Mich,

7 Application August 14, 1936, Serial No. 95,995

3 Claims.

This invention" relatesto an improved intake manifold for and'method of supplying fuel mixture to. internal combustion engines.

More particularly, the invention pertains to 5 improvements in manifolding of V--8'twin, dual'or equivalently carburetted engines.

One of'the' main objects of the invention is to provide relatively short branch passages which present unobstructed passage for the-flow of fuel I 10 mixture to all of the cylinders of an' engine of this character and which, therefore, affords free breathing action.

Another object ofthe invention is to provide a. manifold of this kind in which the air fuel firing orders can "be employed without having two cylinders that are served by a single branch fire or be charged successively, so as to thereby prevent one cylinder from robbinganother cylinder of a portion of its charge.

An additional object of the invention is to provide communication"betweenthe branches of each section of the manifold" which, though restricted enough to cause each branch to draw fuel mixture mainly from its respective carburetting means, is large enough to induce the back surge of fuel mixture occurring in one branch, into the other branch of the same section so as to prevent back flow of the mixture through the carbureter, thus reducing the waste of fuel and the 'fire hazard. V

Another object of the inventionis to provide sections in a manifold of this which. have certainidentical end portions, though reversedin position, so as to enable cores of identical con.- struction to; be used during molding.

A-further object of the inventionis to: provide means for heating. the lower end portions of the inlet passages of the manifold and. which. also surround the restricted. connecting means between-the branches of each: section, respectively,

Fig. 4-- is a; fragmentary, transverse sectional l5 View taken on .theline.44 of Fig-.- 2.

Fig. 5 is. a. fragmentary. transverse sectional view taken on-the-line 5--52-of-Fig.- 2..

Fig. 6 is a diagrammatic illustrational view of the arrangement ofthe manifoldsections and 20 branches andpa'ssageways thereof;

The intake manifold" I0 isdisposedbetween the two banks of" cylinders of the engine 'andit includes two manifold sections, generally. designated by the numerals ll and.l2-in 6. The

manifold section I 2- comprises apair "of branches 1 3 and: I 4 and the. manifold. section :I I comprises a pairof branches [.5 and 16 of which branches I3 and l6"are identical and'branches l5" and M are; identical in structure, though reversed'inr 30 position. The branch l3"'is provldedwith 'opp'ositely extending passageways I! and" 18" which serve cylinders I and VI; respectively. The branch I5 of-the-manifold section I (has a pair of passageways-Hand 22 whichserve cylinders 33 II and V, respectively. The-branch l4-has passageways l9 and 2ll which serve cylinders VII and IV, respectively, andthe branch l6 v haspas sageways 23: and 24 which servecylinders IIIv and VIII, respectively,

Thebranches l3, l4, [5' and i6 are, arranged with. their inner corresponding; ends adjacent, each other as illustrated in Fig. 6, and. each. branch isv provided. with. a riser 25" to each. of. which is connected a substantially independent 45 source of..fue1-.mixtur e. The. sourcespof fuel-mixture may comprise four wholly separate andxin-v dependent. carburetors or a pair of dual carburet'ersmay be employedfor: this purpose}: If desired,i.a.four throat carbureter having .appara.-. tus for. independently, determining. the. fuel mix:- ture characteristics .of. the. fuel supplied to. each respective throat. may be. used. In..the.form: il-. lustratedin.the-drawings, azpair of dual. cars connected together by a conduit 3|.

provided with two fuel mixture throats to which fuel mixture is supplied. Naturally, each carbureter may comprise only one fuel reservoir 28 and 29, respectively, but the fuel mixture throats of the carbureters shown preferably have individual jets for predetermining the fuel mixture ratio therein.

The risers of the branches I3 and M of the manifold section l2 are connected together by a conduit and the risers 25 of the branches l5 and is of the manifold section II are sirniiarly The conduits 3t and 3! are made smaller in cross section than the cross sections of the various branches and passages of the manifold in order to produce relatively restricted communication between the manifold branches at these locations.

An engine equipped with an intake manifold of the foregoing construction can be operated on a plurality of different firing orders while obtain ing the advantages heretofore set forth. Any of the following firing orders may be used. for clockwise rotation of a ninety degree crank shaft in which number two crank pin follows number one crank pin by ninety degrees.

For clockwise rotation of a ninety degree crank shaft in which number two crank pin follows, number one crank pin by 270, the following firing orders may be employed:

For counter-clockwise operation of a ninety degree crank shaft in which number two crank pin follows number one crank pin by ninety degrees the following fire orders may be used:

For counter-clockwise rotation of a ninety degree crank shaft in which number two crank pin follows number one crank pin by 270 degrees, the following firing orders may be used:

In the operation of an engine equipped with a manifold embodying the invention, the distances of travel from the riser to the respective cylinders are relatively short and the passages are substantially unobstructed. These characteristics afford free breathing action of the engine and enable the fuel and air ratio of the fuel mixture produced by the earburetting means to be maintained throughout the entire manifolding system and to the points of entry of fuel mixture to the engine.

During operation of f-S engine on any the foregoing firing orders and having banks of cylinders disposed at ninety degrees to each other and provided with a ninety degree crank shaft of the specified types, successive fuel charges will be supplied to the respective cylinders by different manifold branches. This characteristic of the improved manifolding system prevents one cylinder fromrobbing another cylinder of a portion of its charge, thereby providing a supply of uniform quantities of fuel mixture to all the cylinders.

The conduits 30 and 3| connecting the risers of the branches of the respective manifold sections serve to prevent the back flow of fuel mixture through the carburetting means. This is accomplished without interfering with distribution of fuel mixture by employing conduits which are sufficiently restricted to prevent excessive flow of fuel mixture from the carburetting means of one branch to the other branch, but of large enough size to accommodate the back flow of fuel mixture from one branch to another branch under the suction existing in the last mentioned branch when one of the cylinders which it serves is being charged. In other words, after the cylinder I is charged and the intake valve of that cylinder is closed, the fuel mixture in the branch [3 tends to flow back toward the riser of this branch. Before this back flow can pass through the carburetting means associated with the branch is, one of the cylinders served by the branch E l begins to receive its charge and thereby causes enough suction to induce the back flow through the conduit 30, thereby discouraging the back flow of fuel mixture through the carbureter. This same operation occurs throughout the en- "tire manifolding system and during its entire induction cycle.

In Fig. 3 of the drawings, there is illustrated apparatus for applying heat to the lower end portions of the risers 25 and to the conduits 3i) and 3| by which these risers are connected together.

This structure includesv a heating chamber 3'2 to which a heating medium, preferably exhaust gas from the engine, is supplied by an exhaust gas conduit (not shown). The portions of the walls of the conduits 3d and 3f are disposed in the chamber 32 and these passages are, therefor, effectively heated by the exhaust gases or other heating medium for the purpose of vaporizing any liquid fuel tending to collect in the conduits 3t and 3|.

Although but one specific embodiment of the invention is herein shown and described, it is understood that various changes may be made without departing from the spirit of my invention.

I claim:

1. An intake manifold for a V-8 internal combustion engine having substantially independent carburetting means for each'pair of related cylinders thereof including a pair of manifold sections, each comprising two branches, each branch communicating with one of said carburetting means, respectively, and means providing restricted communication between the inlet end portions of the two branches of each manifold .section, respectively, for preventing blow-back of fuel mixture through said carburetting means, said branches being so constructed and arranged that suction exists in one branch when back flow tends to occur in the other. a a

2; An intake manifold for a V-8 internal comture through said carburetti'ng means, and means for heating portions of said branches comprising an exhaust gas chamber surrounding said communication establishing means for vaporizing liquid fuel tending to collect therein.

3. In a V-8 internal combustion engine having cylinders numbers I, II, III and IV on one side of the central longitudinal axis and cylinders numbers V, VI, VII and VIII on the opposite side of said axis, an intake manifold having substantially independent carburetting means for each pair of related cylinders including a pair of manifold sections, each comprising two branches, the branches of one section, having outlet tubes at their outer ends serving cylinders I and IV respectively and having outlet tubes intermediate their ends serving cylinders VI and VII respectively and the branches of the other section having outlet tubes at their outer ends serving cylinders V and VIII respectively and having outlet tubes intermediate their ends serving cylinders II and III respectively, and means providimg restricted communication between the end portions of the two branches of each manifold section, respectively, for preventing back flow of fuel mixture through said carburetting means, the construction and arrangement of said branches and the firing order of said engine being such that suction occurs in one branch whi1e= blow-back tends to occur in the other branch of said section.

DONNELL A. SULLIVAN. 

